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Maggie McKee writes "The asteroid Apophis has been traversing the void of space for untold years; in just a few decades time it will make a very close pass to Earth, and could make an unwelcome stop on our planet's surface. Even still, it's nothing to get too worked up about. The 20-million-tonne object has a 1 in 45,000 chance of hitting the Pacific Ocean in early April of 2036. If it did hit, it could trigger a tsunami that would do an untold amount of damage to the California coastline and many other places on Earth. Despite the low level of the threat, it's still a real enough danger to prompt the United Nations to develop a protocol about the scenario. We'll get a closeup look at the object in 2029, and at that point we should have a better idea of what 2036 will bring us."

Err... did you read the post you so snottily rebutted? Reading comprehension is almost as important as maths, you know.
People play the lottery, imagining 1:23,000,000 is a good possibility.
Based on that logic, 1:45,000 should be perceived as close to 1:1.

What this says is that every so often something terrible like an asteroid smacking us does happen. What that means is that if the odds are high that this one will hit us, we should actually focus on planning for it like we do with all the other natural disasters instead of ignoring it because it rarely happens. That's like calling nature's bluff, and nature is quite often a very mean poker player. If we have a chance to save lives in a few decades, why not start planning now? It's not wasted energy when someone's life is involved. We already plan for lifesaving in floods, earthquakes, volcanic eruptions, et. al.. Just add "giant tsunami triggered by an asteroid impact wiping the California coastline clean" to your list.

The thing about asteroids and comets is that they are out there in space for us to observe, and we can predict their movements pretty well. That means that unlike an earthquake or a volcano, we can know about an asteroid or comet strike years - even decades in advance. And that means we have time to do something about it. We could actually prevent these disasters. Given that a strike could wipe out the human race entirely, that justs makes it even more prudent to divert some resources to asteroids and c

There are no written accounts, as far as I know, of a meteorite causing significant numbers of human casualties, either through an impact or through a tsunami induced by impact.

Every society on earth has a great flood story woven into their mythology, and many stories of fire and light from "the heavens." Just because they didn't call it a meteorite doesn't mean it didn't happen.

The Tunguska event had the uncanny luck of happening over land and in one of the world's least populated areas. What are the odds of THAT happening again?

The Tunguska event had the uncanny luck of happening over land and in one of the world's least populated areas

It also happened several decades before a nuclear power could misinterpret the event as a first-strike. AFAIK, North American monitoring can tell the difference between something like an asteroid vs. a missile, based on trajectory. They probably coordinate with other types of observers too, since they're monitoring things like space junk already. The irregular streak of a comet or asteroid is

There are no written accounts, as far as I know, of a meteorite causing significant numbers of human casualties, either through an impact or through a tsunami induced by impact.

How would they know that it was a meteorite? Assuming there were survivors to witness it? And of course, tsunami from meteorite impacts would look much like tsunami from earthquakes, volcanos, and undersea landslides.

....I think that there are more commonplace disasters we need to worry about, like earthquakes and tsunamis, which involve more boring, mundane solutions, like good building codes, tsunami warning networks, tsunami evacuation sirens, and flood control.

You worry about those things. Let the Asteroid worriers worry about asteroids. There are billions of us. We can divide the worrying up and not all worry about the same thing. That way when you figure out a way to save us all from earthquakes, you won't immediately drop dead of ebola.

Seriously, if somebody doesn't get a plan for dealing with asteroids, mankind will end. No Earthquake, tsunami, famine, plague, global warming or war will do that. It isn't a question of if the asteroid is coming, but when. It's not likely to hit today, and on the 112th day of 2076 it's equally unlikely. In the fullness of time it's not just likely, it is certain. There is no more "realistic" worry than the certain end of all mankind. If the next dinosaur killer arrives and we have no plan for preventing it or dealing with it, or at least have an offsite backup, there will be no second chance; we will have had our go at Darwin's test and failed. Please -- for the sake of the children -- leave the asteroid scientists to their work.

Oh, and if you figure out a cure for tsunamis that doesn't involve moving our huts further from the sea do please let us know.

One of them is to look at history- written history, archaeology, and geology. There are no written accounts, as far as I know, of a meteorite causing significant numbers of human casualties, either through an impact or through a tsunami induced by impact.

Well, the dinosaurs would have left written accounts, but they were all dead.

More seriously, we do have historical record of even minor meteor showers causing casualties, the biggest reportedly in Chiing-yang, China in 1490, in an apparent Tunguska-like event, killing a possible "tens of thousands". Mostly its onesies and twosies, though. Tunguska itself, detonating in the middle of nowhere, Sibera, injured the 20 people who were within 50 km of the blast, and killed two. Thousands of reindeer were killed.

Should Apophis (or something that size) hit Earth, the energy release would be about 10 to 20 times that of the Tunguska or Arizona impacts (those were in the 10-20 megaton range), and about 2 or 3 times that of the Krakatoa explosion. Since 3/4 of the planet is water-covered, odds are that most large impacts hit water and cause damage through the result tsunamis. (And yes, we get a few in the several-kiloton range each year - mostly in the middle of nowhere - as has been documented by surveillance satellites.)

Sure, Apophis is no Dinosaur Killer, but it could cause quite a mess depending on if and where it hits.

There are no written accounts, as far as I know, of a meteorite causing significant numbers of human casualties, either through an impact or through a tsunami induced by impact.

Then the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven; and he overthrew those cities, and all the plain, and all the inhabitants of the cities, and that which grew upon the ground.

They don't know exactly where it will intersect Earth's orbit, but they do know, within an hour or two when it will cross our path. At that time of day (or night, whatever) the Pacific Ocean will be more or less facing the direction the asteroid's coming from. Given the size of the Pacific it's reasonably likely that if the asteroid does hit Earth, it'll be somewhere there.

Scientists may also have an idea of the latitude or longitude it will hit, narrowing the window further.

That's the great untold thing about this story. For untold years, slashdot editors have been writing untold dupes, while governments around the world have been avoiding getting their untold shit together for untold years. When will the untold story be told?

This will, however effect my plans of building a cryogenic chamber to freeze myself until they year 5,000,000,000,000. I would hate for the subtraction to overflow, and wake up in the year 707,722,973,404 BC. Actually, come to think of it, it would be interesting to see the universe before it was actually created.

The US government was able to pull off Apollo in 8 years, and that was having to develop a lot of new technology instead of simply reimplementing them. I think that serious of a threat would allow even a single government to be able to devote the funds to be able to complete such a project in time.

In science-fiction writer Michael Flynn's future history starting with the novel Firestar [amazon.com] , it's actually the fear of an asteroid that gets a corporate executive starting commercial space travel, jumping ahead of inefficient and bureacratic NASA. Well, it's been a few years now since the date Flynn suggested for the start of real orbital travel, not just the suborbital tourism we're seeing developed now. But nonetheless, I'd like to think that in the last couple of years we're showing enough progress that

1) Set up shop and charge maybe... one billion dollars for a spot on a martian/lunar/orbital station. Charge even more for the luxury suites where you don't need to perform grueling physical labor.
2) Convince the uber-wealthy that there is a chance (maybe 1% is enough?) that all life on earth will be wiped out, the only way to ensure survival is to move onto the off-world colony.
3) Profit!
4) ?????

Apophis is not a doomsday asteroid. It will cause a major disaster for a large area if it hits, but it should not be a threat to the survival of humanity to the extent that we need to build space colonies to avoid eradication.

1. set up an alert system:
>>(green, no asteroid)
>>(yellow, the asteroid MIGHT be near the earth)
>>(orange, be careful when answering your door, IT MIGHT BE THE ASTEROID!)
>>(red, we're already dead from the impact)

2. earmark government funds to buy swimsuits and surfboards for all californians

3. have congressional prayer sessions thanking the intelligent designer for wiping out the seat of all vice

Figuring out the exact speed of an asteroid, relative to us, is apparently a tad easier than figuring out its exact course. According to the data we have, the possible path of the asteriod is a cone.... the earth is inside that cone currently. Earth takes up about 1/45,000th of that cone, specifically. We know when it will get here, if it does get here, with a good degree of accuracy. And we know what direction it would be coming from. So that rules out it landing in, say, Cuba - it would be coming from the wrong direction to hit there at the time of impact.

To be honest I still don't get it. I get that we're in the cone of possible projected paths for this thing. But surely that's one whole side of the Earth that's in it. If we can calculate the precise time in which it would hit us then I can obviously see that maybe the Californian coastline might be smack in the centre of the Earth relative to the asteroid, but surely that still means there's only a tiny fraction of the 1/45000 chance that it will actually hit dead centre. No?

Nevermind. Just paid a bit more attention to TFA and realised they're talking about it hitting "the pacific ocean", not specifically the Californian coastline, in which case they probably can safely make that assumption if the timing were just right.

The target zone is apparently a path from Siberia leading ESE through North America around to the west coast of Africa. I don't understand it myself, since the uncertainty should be a conic region giving us a more-or-less circular target zone on the surface of the Earth (not linear).So far as the report on New Scientist goes, I guess they just decided to say it would hit the Pacific off the coast of California. The artists' impression picture is also not to scale - an asteroid that big relative to Earth wou

Actually, the uncertainty mostly isn't due to error in position; it's due to the fact that, when we observe a NEO, it's a point of light in the sky. We really don't know how far away it is. If it's near to the Earth and Sun, it moves more quickly; if it's farther away, it moves more slowly. If you remember that things move in circles or ellipses around the Sun, then you might get the idea that the uncertainty "ellipse" (due to a small error in position left-right, but a very large error in depth) due to the different orbital velocities, it "stretches out" over time, wrapping the ellipse's major axis around the Sun until it's basically a straight line.

There's a fantastic animation of this process at Spaceguard's [esa.int] site, just scroll down to the second animation.

We don't, but since most of the earth is covered by the Pacific ocean, chances are better than 70% that it will hit there. If we are really lucky, it will hit Washington DC, but the odds are against us...

The PTS relates the impact risk to the background risk in a logarithmic way -- that is, the probability of Apophis hitting us is 0.003 times the probability that we will be struck by some other asteroid of equal or larger size first. Or, put another way, yes we should be worried about asteroid impacts, and yes we should keep watching Apophis, but it's not (by our understanding) a big cause to go and panic.

That said, Apophis is the second highest ranked asteroid we know about by the PTS, behind 2007 CA19 at -0.91 (potential impact in 2012). And if it gets the people with the budgets to start considering the problem, that's a good thing. Right now, though, it would seem that our best use of money is to spend more effort looking for asteroids -- so far, the number we find appears to be fairly well correlated to how hard we look, suggesting that we have found a very, very small fraction of the NEOs out there.

The object 2007 CA19 [nasa.gov] has a better chance (as of right now) of hitting the Earth than 99942 Apophis (2004 MN4) [nasa.gov] does. The former is also about four times larger than the latter and would have more than double the velocity at impact if it were to hit.

The impact probability for 2007_CA19 is based on a bit over 5 days of observations. Further observations are more likely to decrease impact probability than to increase it. It is definitely worth keeping an eye on, but I wouldn't take impact probabilities too seriously until a few more weeks of observations have taken place.

To put this into perspective you have roughly a 1 in 80,000 chance of dying from an act of terrorism, almost twice the odds that this thing will strike the Earth. Now think about that. The odds of this think hitting the PLANET is greater than any 1 person being killed by a terrorist. Now look back at how much time and money has been spent on combating those that use terrorism to accomplish their goals.

Think about it where our priorities should be.

For reference, Meteor Crater in Arizona, which is about a mile wide and 500 feet deep, was created by a ~66' wide meteor. Apophis is ~450' wide. If another meteor the size of the one from Arizona were to hit a city, which is twice as likely to happen than a terrorist strike, it'd be akin to a nuclear detonation. If something the size of Apophis should strike the earth, well, say goodbye to whatever county (or small state) it lands in.

One thing we should worry about is a prediction of an impact in a large population centre. For example a 1 in 100 probability of an impact in India in 10 years. The result of such a prediction would be much worse than the actual impact.

If another meteor the size of the one from Arizona were to hit a city, which is twice as likely to happen than a terrorist strike, it'd be akin to a nuclear detonation. If something the size of Apophis should strike the earth, well, say goodbye to whatever county (or small state) it lands in.

If this puppy is aimed at the USA then I sure hope Canada sets up a system that requires passports and all sorts of red tape for anyone from the USA who wishes to visit our country!

20 million tons? Probably flying into the Earth at near light speeds? And you fools think it's just going to do some coastal damage to California? From where I come from this sounds like a formula for breaking the Earth into millions of little shards. The only living things that would survive would be small things like cockroaches that would be able to cling onto their own bit of rock and survive the recoagulation of the planet. Mankind would likely be wiped from the face of the Earth (not too much of

The article mentions that potential 'threat asteroids' are being tracked, and hopefully all potential threats will soon be identified for closer observation.I remember reading years ago on slashdot about a near-miss that occured during daylight hours, when a global-catastrophe sized asteroid approached earth from the sun and passed between the moon and earth. Does anybody remember this? And the asteroid wasn't even detected until it had already passed.

This asteroid has been known about since 2004. The odds of it striking earth have been changed several times, the last time in October 2006 when the odds were actually decreased. What's the story here again?

Statistically it's most likly to hit there because it's the largest named area? I don't know, I agree it sounds a bit fishy (npi) - maybe they figure if Google and MS are in the way of a potential tsunami, one or the other will figure out a solution. *shrug*

Unless they get more precise knowledge of the orbit, intervention right now could be worse than doing nothing. You might, for example, accidentally turn what would have been a near miss into a direct hit. The most useful course of action right now would probably be to deposit some sort of radio beacon on the asteroid in order to increase the accuracy of the orbital measurements.